mtd: nand: fix bug writing 1 byte less than page size

nand_do_write_ops() determines if it is writing a partial page with the
formula:
	part_pagewr = (column || writelen < (mtd->writesize - 1))

When 'writelen' is exactly 1 byte less than the NAND page size the formula
equates to zero, so the code doesn't process it as a partial write, although
it should.
As a consequence the function remains in the while(1) loop with 'writelen'
becoming 0xffffffff and iterating until the watchdog timeout triggers.

To reproduce the issue on a NAND with 2K page (0x800):
	=> nand erase.part <partition>
	=> nand write $loadaddr <partition> 7ff

Signed-off-by: Hector Palacios <hector.palacios@digi.com>

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 4cf45189896c6004761a877e08944ab375a9784d..d1287bc3be9f880d4776683d8f4d267e3f34d643 100644 (file)
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2414,7 +2414,7 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
                int cached = writelen > bytes && page != blockmask;
                uint8_t *wbuf = buf;
                int use_bufpoi;
-               int part_pagewr = (column || writelen < (mtd->writesize - 1));
+               int part_pagewr = (column || writelen < mtd->writesize);
 
                if (part_pagewr)
                        use_bufpoi = 1;